the list is not in any order.
picking a best would be too difficult.
with the exception of stephenson & pohl, each of the authors has a body of work that includes few if any weak novels.
stephenson only has only published a few novels.
pohl has been writting for many decades. The novels written in the 70s are some of the best novels ever written. he has written so many novels, there are weak entries.
Heinlein gets a notable mention (Moon is a Harsh Mistress is his best)
lets throw in two more notables - Dune by frank herbert & the Eden series by Harry Harrison